rtp: h264: Move profile_level_id parsing to a function
[libav.git] / libavformat / rtpdec_h264.c
1 /*
2 * RTP H264 Protocol (RFC3984)
3 * Copyright (c) 2006 Ryan Martell
4 *
5 * This file is part of Libav.
6 *
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * @brief H.264 / RTP Code (RFC3984)
25 * @author Ryan Martell <rdm4@martellventures.com>
26 *
27 * @note Notes:
28 * Notes:
29 * This currently supports packetization mode:
30 * Single Nal Unit Mode (0), or
31 * Non-Interleaved Mode (1). It currently does not support
32 * Interleaved Mode (2). (This requires implementing STAP-B, MTAP16, MTAP24,
33 * FU-B packet types)
34 */
35
36 #include "libavutil/attributes.h"
37 #include "libavutil/base64.h"
38 #include "libavutil/avstring.h"
39 #include "libavcodec/get_bits.h"
40 #include "avformat.h"
41
42 #include "network.h"
43 #include <assert.h>
44
45 #include "rtpdec.h"
46 #include "rtpdec_formats.h"
47
48 struct PayloadContext {
49 // sdp setup parameters
50 uint8_t profile_idc;
51 uint8_t profile_iop;
52 uint8_t level_idc;
53 int packetization_mode;
54 #ifdef DEBUG
55 int packet_types_received[32];
56 #endif
57 };
58
59 #ifdef DEBUG
60 #define COUNT_NAL_TYPE(data, nal) data->packet_types_received[(nal) & 0x1f]++
61 #else
62 #define COUNT_NAL_TYPE(data, nal) do { } while (0)
63 #endif
64
65 static const uint8_t start_sequence[] = { 0, 0, 0, 1 };
66
67 static void parse_profile_level_id(AVFormatContext *s,
68 PayloadContext *h264_data,
69 char *value)
70 {
71 char buffer[3];
72 // 6 characters=3 bytes, in hex.
73 uint8_t profile_idc;
74 uint8_t profile_iop;
75 uint8_t level_idc;
76
77 buffer[0] = value[0];
78 buffer[1] = value[1];
79 buffer[2] = '\0';
80 profile_idc = strtol(buffer, NULL, 16);
81 buffer[0] = value[2];
82 buffer[1] = value[3];
83 profile_iop = strtol(buffer, NULL, 16);
84 buffer[0] = value[4];
85 buffer[1] = value[5];
86 level_idc = strtol(buffer, NULL, 16);
87
88 av_log(s, AV_LOG_DEBUG,
89 "RTP Profile IDC: %x Profile IOP: %x Level: %x\n",
90 profile_idc, profile_iop, level_idc);
91 h264_data->profile_idc = profile_idc;
92 h264_data->profile_iop = profile_iop;
93 h264_data->level_idc = level_idc;
94 }
95
96 static int sdp_parse_fmtp_config_h264(AVFormatContext *s,
97 AVStream *stream,
98 PayloadContext *h264_data,
99 char *attr, char *value)
100 {
101 AVCodecContext *codec = stream->codec;
102 assert(codec->codec_id == AV_CODEC_ID_H264);
103 assert(h264_data != NULL);
104
105 if (!strcmp(attr, "packetization-mode")) {
106 av_log(s, AV_LOG_DEBUG, "RTP Packetization Mode: %d\n", atoi(value));
107 h264_data->packetization_mode = atoi(value);
108 /*
109 * Packetization Mode:
110 * 0 or not present: Single NAL mode (Only nals from 1-23 are allowed)
111 * 1: Non-interleaved Mode: 1-23, 24 (STAP-A), 28 (FU-A) are allowed.
112 * 2: Interleaved Mode: 25 (STAP-B), 26 (MTAP16), 27 (MTAP24), 28 (FU-A),
113 * and 29 (FU-B) are allowed.
114 */
115 if (h264_data->packetization_mode > 1)
116 av_log(s, AV_LOG_ERROR,
117 "Interleaved RTP mode is not supported yet.\n");
118 } else if (!strcmp(attr, "profile-level-id")) {
119 if (strlen(value) == 6)
120 parse_profile_level_id(s, h264_data, value);
121 } else if (!strcmp(attr, "sprop-parameter-sets")) {
122 codec->extradata_size = 0;
123 av_freep(&codec->extradata);
124
125 while (*value) {
126 char base64packet[1024];
127 uint8_t decoded_packet[1024];
128 int packet_size;
129 char *dst = base64packet;
130
131 while (*value && *value != ','
132 && (dst - base64packet) < sizeof(base64packet) - 1) {
133 *dst++ = *value++;
134 }
135 *dst++ = '\0';
136
137 if (*value == ',')
138 value++;
139
140 packet_size = av_base64_decode(decoded_packet, base64packet,
141 sizeof(decoded_packet));
142 if (packet_size > 0) {
143 uint8_t *dest = av_malloc(packet_size + sizeof(start_sequence) +
144 codec->extradata_size +
145 FF_INPUT_BUFFER_PADDING_SIZE);
146 if (!dest) {
147 av_log(s, AV_LOG_ERROR,
148 "Unable to allocate memory for extradata!\n");
149 return AVERROR(ENOMEM);
150 }
151 if (codec->extradata_size) {
152 memcpy(dest, codec->extradata, codec->extradata_size);
153 av_free(codec->extradata);
154 }
155
156 memcpy(dest + codec->extradata_size, start_sequence,
157 sizeof(start_sequence));
158 memcpy(dest + codec->extradata_size + sizeof(start_sequence),
159 decoded_packet, packet_size);
160 memset(dest + codec->extradata_size + sizeof(start_sequence) +
161 packet_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
162
163 codec->extradata = dest;
164 codec->extradata_size += sizeof(start_sequence) + packet_size;
165 }
166 }
167 av_log(s, AV_LOG_DEBUG, "Extradata set to %p (size: %d)!\n",
168 codec->extradata, codec->extradata_size);
169 }
170 return 0;
171 }
172
173 // return 0 on packet, no more left, 1 on packet, 1 on partial packet
174 static int h264_handle_packet(AVFormatContext *ctx, PayloadContext *data,
175 AVStream *st, AVPacket *pkt, uint32_t *timestamp,
176 const uint8_t *buf, int len, uint16_t seq,
177 int flags)
178 {
179 uint8_t nal;
180 uint8_t type;
181 int result = 0;
182
183 if (!len) {
184 av_log(ctx, AV_LOG_ERROR, "Empty H264 RTP packet\n");
185 return AVERROR_INVALIDDATA;
186 }
187 nal = buf[0];
188 type = nal & 0x1f;
189
190 assert(data);
191 assert(buf);
192
193 /* Simplify the case (these are all the nal types used internally by
194 * the h264 codec). */
195 if (type >= 1 && type <= 23)
196 type = 1;
197 switch (type) {
198 case 0: // undefined, but pass them through
199 case 1:
200 if ((result = av_new_packet(pkt, len + sizeof(start_sequence))) < 0)
201 return result;
202 memcpy(pkt->data, start_sequence, sizeof(start_sequence));
203 memcpy(pkt->data + sizeof(start_sequence), buf, len);
204 COUNT_NAL_TYPE(data, nal);
205 break;
206
207 case 24: // STAP-A (one packet, multiple nals)
208 // consume the STAP-A NAL
209 buf++;
210 len--;
211 // first we are going to figure out the total size
212 {
213 int pass = 0;
214 int total_length = 0;
215 uint8_t *dst = NULL;
216
217 for (pass = 0; pass < 2; pass++) {
218 const uint8_t *src = buf;
219 int src_len = len;
220
221 while (src_len > 2) {
222 uint16_t nal_size = AV_RB16(src);
223
224 // consume the length of the aggregate
225 src += 2;
226 src_len -= 2;
227
228 if (nal_size <= src_len) {
229 if (pass == 0) {
230 // counting
231 total_length += sizeof(start_sequence) + nal_size;
232 } else {
233 // copying
234 assert(dst);
235 memcpy(dst, start_sequence, sizeof(start_sequence));
236 dst += sizeof(start_sequence);
237 memcpy(dst, src, nal_size);
238 COUNT_NAL_TYPE(data, *src);
239 dst += nal_size;
240 }
241 } else {
242 av_log(ctx, AV_LOG_ERROR,
243 "nal size exceeds length: %d %d\n", nal_size, src_len);
244 }
245
246 // eat what we handled
247 src += nal_size;
248 src_len -= nal_size;
249
250 if (src_len < 0)
251 av_log(ctx, AV_LOG_ERROR,
252 "Consumed more bytes than we got! (%d)\n", src_len);
253 }
254
255 if (pass == 0) {
256 /* now we know the total size of the packet (with the
257 * start sequences added) */
258 if ((result = av_new_packet(pkt, total_length)) < 0)
259 return result;
260 dst = pkt->data;
261 } else {
262 assert(dst - pkt->data == total_length);
263 }
264 }
265 }
266 break;
267
268 case 25: // STAP-B
269 case 26: // MTAP-16
270 case 27: // MTAP-24
271 case 29: // FU-B
272 av_log(ctx, AV_LOG_ERROR,
273 "Unhandled type (%d) (See RFC for implementation details\n",
274 type);
275 result = AVERROR(ENOSYS);
276 break;
277
278 case 28: // FU-A (fragmented nal)
279 buf++;
280 len--; // skip the fu_indicator
281 if (len > 1) {
282 // these are the same as above, we just redo them here for clarity
283 uint8_t fu_indicator = nal;
284 uint8_t fu_header = *buf;
285 uint8_t start_bit = fu_header >> 7;
286 uint8_t av_unused end_bit = (fu_header & 0x40) >> 6;
287 uint8_t nal_type = fu_header & 0x1f;
288 uint8_t reconstructed_nal;
289
290 // Reconstruct this packet's true nal; only the data follows.
291 /* The original nal forbidden bit and NRI are stored in this
292 * packet's nal. */
293 reconstructed_nal = fu_indicator & 0xe0;
294 reconstructed_nal |= nal_type;
295
296 // skip the fu_header
297 buf++;
298 len--;
299
300 if (start_bit)
301 COUNT_NAL_TYPE(data, nal_type);
302 if (start_bit) {
303 /* copy in the start sequence, and the reconstructed nal */
304 if ((result = av_new_packet(pkt, sizeof(start_sequence) + sizeof(nal) + len)) < 0)
305 return result;
306 memcpy(pkt->data, start_sequence, sizeof(start_sequence));
307 pkt->data[sizeof(start_sequence)] = reconstructed_nal;
308 memcpy(pkt->data + sizeof(start_sequence) + sizeof(nal), buf, len);
309 } else {
310 if ((result = av_new_packet(pkt, len)) < 0)
311 return result;
312 memcpy(pkt->data, buf, len);
313 }
314 } else {
315 av_log(ctx, AV_LOG_ERROR, "Too short data for FU-A H264 RTP packet\n");
316 result = AVERROR_INVALIDDATA;
317 }
318 break;
319
320 case 30: // undefined
321 case 31: // undefined
322 default:
323 av_log(ctx, AV_LOG_ERROR, "Undefined type (%d)\n", type);
324 result = AVERROR_INVALIDDATA;
325 break;
326 }
327
328 pkt->stream_index = st->index;
329
330 return result;
331 }
332
333 static PayloadContext *h264_new_context(void)
334 {
335 return av_mallocz(sizeof(PayloadContext) + FF_INPUT_BUFFER_PADDING_SIZE);
336 }
337
338 static void h264_free_context(PayloadContext *data)
339 {
340 #ifdef DEBUG
341 int ii;
342
343 for (ii = 0; ii < 32; ii++) {
344 if (data->packet_types_received[ii])
345 av_log(NULL, AV_LOG_DEBUG, "Received %d packets of type %d\n",
346 data->packet_types_received[ii], ii);
347 }
348 #endif
349
350 av_free(data);
351 }
352
353 static av_cold int h264_init(AVFormatContext *s, int st_index,
354 PayloadContext *data)
355 {
356 if (st_index < 0)
357 return 0;
358 s->streams[st_index]->need_parsing = AVSTREAM_PARSE_FULL;
359 return 0;
360 }
361
362 static int parse_h264_sdp_line(AVFormatContext *s, int st_index,
363 PayloadContext *h264_data, const char *line)
364 {
365 AVStream *stream;
366 AVCodecContext *codec;
367 const char *p = line;
368
369 if (st_index < 0)
370 return 0;
371
372 stream = s->streams[st_index];
373 codec = stream->codec;
374
375 if (av_strstart(p, "framesize:", &p)) {
376 char buf1[50];
377 char *dst = buf1;
378
379 // remove the protocol identifier
380 while (*p && *p == ' ')
381 p++; // strip spaces.
382 while (*p && *p != ' ')
383 p++; // eat protocol identifier
384 while (*p && *p == ' ')
385 p++; // strip trailing spaces.
386 while (*p && *p != '-' && (dst - buf1) < sizeof(buf1) - 1)
387 *dst++ = *p++;
388 *dst = '\0';
389
390 // a='framesize:96 320-240'
391 // set our parameters
392 codec->width = atoi(buf1);
393 codec->height = atoi(p + 1); // skip the -
394 } else if (av_strstart(p, "fmtp:", &p)) {
395 return ff_parse_fmtp(s, stream, h264_data, p, sdp_parse_fmtp_config_h264);
396 } else if (av_strstart(p, "cliprect:", &p)) {
397 // could use this if we wanted.
398 }
399
400 return 0;
401 }
402
403 RTPDynamicProtocolHandler ff_h264_dynamic_handler = {
404 .enc_name = "H264",
405 .codec_type = AVMEDIA_TYPE_VIDEO,
406 .codec_id = AV_CODEC_ID_H264,
407 .init = h264_init,
408 .parse_sdp_a_line = parse_h264_sdp_line,
409 .alloc = h264_new_context,
410 .free = h264_free_context,
411 .parse_packet = h264_handle_packet
412 };